液态金属电极的电化学储能应用

doi:10.13208/j.electrochem.200652

摘要/Abstract

摘要：

液态金属电极电导率高,电极界面容易构建,在充放电过程中可有效避免电极结构形变、枝晶生长等问题,在储能电池领域具有重要应用价值. 本文主要讨论了液态金属电极在液态金属电池、钠硫电池和ZEBRA电池中的应用进展,重点介绍了液态金属电池关键材料体系、充放电机制及电池构型等,评述了液态金属电极储能应用中涉及的熔盐电解质、固态陶瓷隔膜、多场影响因素等方面的重要研究进展,分析了高温密封、腐蚀防护等关键问题,明确了液态金属电极在储能电池应用中的发展方向.

关键词: 电化学储能, 液态金属电极, 液态金属电池, 钠硫电池, ZEBRA电池

Abstract:

Electrochemical energy storage technologies (ESTs) with low cost, long lifespan and high safety are of great importance for efficient integration of renewable energy into the grid. Liquid metal electrodes (LMEs) possessing the merits of high electronic conductivity, easy manufacture and amorphous structure is of great application value in the field of energy storage batteries. During charge-discharge processing, the LMEs could avoid the issues of structural deformation and dendrite growth in solid metal electrodes, which could effectively extend the cycle life of the LME based batteries. Moreover, LME based batteries are easy to be scaled up and less expensive, which are well-positioned to satisfy the demands of grid-scale energy storage. In this paper, the state-of-the-art overview of LMEs in batteries including liquid metal batteries (LMBs), sodium-sulfur (Na||S) and ZEBRA (Na||NiCl₂) batteries is presented. The materials systems, reaction mechanisms and novel designing in LMBs are emphatically discussed. Besides the LMEs, the developments of the molten salts electrolytes and solid state electrolytes, and the multi-field coupled flows inside LMBs are summarized. The challenges for the applications of LMEs in the batteries, such as high temperature sealing and corrosion, are discussed. Finally, the prospects of the application of LMEs in the field of the ESTs are also described.

Key words: electrochemical energy storage, liquid metal electrodes, liquid metal batteries, Na, S batteries, ZEBRA batteries

中图分类号:

O646

李浩秒, 周浩, 王康丽, 蒋凯. 液态金属电极的电化学储能应用[J]. 电化学（中英文）, 2020, 26(5): 663-682.

LI Hao-miao, ZHOU Hao, WANG Kang-li, JIANG Kai. Liquid Metal Electrodes for Electrochemical Energy Storage Technologies[J]. Journal of Electrochemistry, 2020, 26(5): 663-682.

导出引用管理器 EndNote|Ris|BibTeX

链接本文: https://electrochem.xmu.edu.cn/CN/10.13208/j.electrochem.200652

https://electrochem.xmu.edu.cn/CN/Y2020/V26/I5/663

图/表 17

图1

图2

图3

图4

图5

表1

图6

图7

图8

图9

图10

图11

图12

图13

表5

图14

图15

参考文献 91

[1]	Yang Z G, Zhang J L, Kintner-Meyer M C W, et al. Electrochemical energy storage for green grid[J]. Chemical Reviews, 2011,111(5):3577-3613. URL pmid: 21375330
[2]	Faisal M, Hannan M A, Ker P J, et al. Review of energy storage system technologies in microgrid applications: issues and challenges[J]. IEEE Access, 2018,6:35143-35164. doi: 10.1109/Access.6287639 URL
[3]	Dunn B, Kamath H, Tarascon J M. Electrical energy storage for the grid: a battery of choices[J]. Science, 2011,334(6058):928-935. URL pmid: 22096188
[4]	Li X F(李先锋), Zhang H Z(张洪章), Zheng Q(郑琼), et al. Electrochemical energy storage technology in energy revolution[J]. Bulletin of Chinese Academy of Sciences (中国科学院院刊), 2019,34(4):443-449.
[5]	Liu D H, Bai Z G, Li M, et al. Developing high safety Li-metal anodes for future high-energy Li-metal batteries: strategies and perspectives[J]. Chemical Society Reviews, 2020,49(15):5407-5445. URL pmid: 32658219
[6]	Zhang N, Chen X Y, Yu M, et al. Materials chemistry for rechargeable zinc-ion batteries[J]. Chemical Society Reviews, 2020,49(13):4203-4219. doi: 10.1039/c9cs00349e URL pmid: 32478772
[7]	Rana M, Ahad S A, Li M, et al. Review on areal capacities and long-term cycling performances of lithium sulfur battery at high sulfur loading[J]. Energy Storage Materials, 2019,18:289-310. doi: 10.1016/j.ensm.2018.12.024 URL
[8]	Lin M C, Gong M, Lu B, et al. An ultrafast rechargeable aluminium-ion battery[J]. Nature, 2015,520(7547):324-328. doi: 10.1038/nature14340 URL
[9]	Chen H, Gao F, Liu Y J, et al. A defect-free principle for advanced graphene cathode of aluminum-ion battery[J]. Advanced Materials, 2017,26(12):1605958.
[10]	Dey A. Electrochemical alloying of lithium in organic electrolytes[J]. Journal of the Electrochemistry Society, 1971,118(10):1547-1549. doi: 10.1149/1.2407783 URL
[11]	Whittingham M S. Lithium batteries and cathode materials[J]. Chemical Reviews, 2004,104(10):4271-4302. doi: 10.1021/cr020731c URL pmid: 15669156
[12]	Zhang Y, Wang C W, Pastel G, et al. 3D wettable framework for dendrite-free alkali metal anodes[J]. Advanced Energy Materials, 2018,8(18):1800635. doi: 10.1002/aenm.201800635 URL
[13]	Li H M, Yin H Y, Wang K L, et al. Liquid metal electrodes for energy storage batteries[J]. Advanced Energy Materials, 2016,6(14):1600483. doi: 10.1002/aenm.201600483 URL
[14]	Wen Z Y, Hu Y Y, Wu X W, et al. Main challenges for high performance NAS battery: Materials and interfaces[J] Advanced Functional Materials 2013,23(8):1005-1018. doi: 10.1002/adfm.v23.8 URL
[15]	Hueso K B, Armand M, Rojo T. High temperature sodium batteries: status, challenges and future trends[J]. Energy & Environmental Science, 2013,6(3):734-749.
[16]	Ellis B L, Nazar L F. Sodium and sodium-ion energy storage batteries[J]. Current Opinion in Solid State & Materials Science, 2012,16(4):168-177.
[17]	Yu Z L, Fang S, Yang J Y, et al. In-situ growth of silicon nanowires on graphite by molten salt electrolysis for high performance lithium-ion batteries[J]. Materials Letters, 2020,273:127946. doi: 10.1016/j.matlet.2020.127946 URL
[18]	Xiao W(肖巍), Zhu H(朱华), Yin H Y(尹华意), et al. Novel molten-salt electrolysis processes towards low-carbon metallurgy[J]. Journal of Electrochemistry (电化学), 2012,18(3):193-200.
[19]	Li Z H(黎朝晖), Zhu F F(朱方方), Li H M(李浩秒), et al. Research progresses of liquid metal batteries[J]. Energy Storage Science and Technology (储能科学与技术), 2017,6(5):981-989.
[20]	Thackeray M M, Wolverton C, Isaacs E D. Electrical energy storage for transportation-approaching the limits of, and going beyond, lithium-ion batteries[J]. Energy & Environmental Science, 2012,5(7):7854-7863.
[21]	Weppner W, Huggins R A. Thermodynamic properties of the intermetallic systems lithium-antimony and lithium-bismuth[J]. Journal of The Electrochemical Society, 1978,9(1):7-14.
[22]	Shimotake H, Rogers G L, Cairns E J, et al. Secondary cells with lithium anodes and immobilized fused-salt electrolytes[J]. Industrial & Engineering Chemistry Process Design and Development, 1969,8(1):51-56.
[23]	Ning X H, Phadke S, Chung B, et al. Self-healing Li-Bi liquid metal battery for grid-scale energy storage[J]. Journal of Power Sources, 2015,275:370-376. doi: 10.1016/j.jpowsour.2014.10.173 URL
[24]	Cairns, E J, Crouthamel, C E, Fischer, A, et al. Galvanic cells with fused-salt electrolytes[D]. United States: Argonne National Laboratory, 1967.
[25]	Shimotake H, E Cairns. Bimetallic galvanic cells with fused salt electrolyte[D]. New York: American Society of Mechanical Engineers, 1967.
[26]	Newhouse J M, Poizeau S, Kim H, et al. Thermodynamic properties of calcium-magnesium alloys determined by emf measurements[J]. Electrochimica Acta, 2013,91:293-301. doi: 10.1016/j.electacta.2012.11.063 URL
[27]	Wen, John C, Huggins R A. Thermodynamic study of the lithium-tin system[J]. Journal of The Electrochemical Society, 1981,128(6):1181-1187. doi: 10.1149/1.2127590 URL
[28]	Tamaki S, Ishiguro T, Takeda S. Thermodynamic properties of liquid Na-Sn alloys[J]. Journal of Physics F - Metal Physics, 1982,12(8):1613-1624. doi: 10.1088/0305-4608/12/8/008 URL
[29]	Saboungi M, Marr J J, Blander M, et al. Thermodynamic properties of a quasi-ionic alloy from electromotive force measurements: The Li-Pb system[J]. Journal of Chemical Physics, 1978,68(4):1375-1384. doi: 10.1063/1.435957 URL
[30]	Wang K L, Jiang K, Chung B, et al. Lithium-antimony-lead liquid metal battery for grid-level energy storage[J]. Nature, 2014,514(7522):348-350. doi: 10.1038/nature13700 URL
[31]	Anonymous. Ambri's better grid battery[J]. Advanced Battery Technology, 2013,49(3):13-14.
[32]	Li H M, Wang K L, Cheng S J, et al. High performance liquid metal battery with environmentally friendly antimony-tin positive electrode[J]. ACS Applied Materials & Interfaces, 2016,8(20):12830-12835. URL pmid: 27149506
[33]	Dai T, Zhao Y, Ning X H, et al. Capacity extended bismuth-antimony cathode for high-performance liquid metal battery[J]. Journal of Power Sources, 2018,381:38-45. doi: 10.1016/j.jpowsour.2018.01.048 URL
[34]	Zhao W, Li P, Liu Z W, et al. High-performance antimony-bismuth-tin positive electrode for liquid metal battery[J]. Chemistry of Materials, 2018,30(24):8739-8746.
[35]	Songster J, Pelton A. The Li-Te (lithium-tellurium) system[J]. Journal of Phase Equilibria and Diffusion, 1992,13:300-303.
[36]	Li H M, Wang K L, Zhou H, et al. Tellurium-tin based electrodes enabling liquid metal batteries for high specific energy storage applications[J]. Energy Storage Materials, 2018,14:267-271.
[37]	Matsunaga S, Ishiguro T, Tamaki S. Thermodynamic properties of liquid Na-Pb alloys[J]. Journal of Physics F- Metal Physics, 1983,13(3):587-595.
[38]	Neale F E, Cusack N E. Thermodynamic properties of liquid sodium-caesium alloys[J]. Journal of Physics F - Metal Physics, 1982,12(12):2839-2850.
[39]	Weaver R D, Smith S W, Willmann N L. The sodium-tin liquid-metal cell[J]. Journal of The Electrochemical Society, 1962,109(8):653-657.
[40]	Kim H, Boysen D A, Newhouse J M, et al. Liquid metal batteries: past, present, and future[J]. Chemical Reviews, 2013,113(3):2075-2099. URL pmid: 23186356
[41]	Cairns E, Gay E, Steunenberg R, et al. Development of high specific energy batteries for electric vehicles[D]. Chicago: Argonne National Lab, 1972.
[42]	Gay E C, Arntzen J D, Cairns E J, et al. Lithium chalcogen secondary cells for components in electric vehicular propulsion generating systems[D]. Chicago: Argonne National Laboratory, 1972.
[43]	Hesson J C, Foster M S, Shimotake H. Self-discharge in alkali metal-containing bimetallic cells[J]. Journal of The Electrochemical Society, 1968,115(8):787-790. doi: 10.1149/1.2411431 URL
[44]	Bradwell D J, Kim H, Sirk A H C, et al. Magnesium-antimony liquid metal battery for stationary energy storage[J]. Journal of the American Chemical Society, 2012,134(4):1895-1897. doi: 10.1021/ja209759s URL pmid: 22224420
[45]	Poizeau S, Kim H, Newhouse J M, et al. Determination and modeling of the thermodynamic properties of liquid calcium-antimony alloys[J]. Electrochimica Acta, 2012,76:8-15. doi: 10.1016/j.electacta.2012.04.139 URL
[46]	Kim H, Boysen D A, Bradwell D J, et al. Thermodynamic properties of calcium-bismuth alloys determined by emf measurements[J]. Electrochimica Acta, 2012,60:154-162. doi: 10.1016/j.electacta.2011.11.023 URL
[47]	Ouchi T, Kim H, Spatocco B L, et al. Calcium-based multi-element chemistry for grid-scale electrochemical energy storage[J]. Nature Communications, 2016,7(1):10999.
[48]	Kim H, Boysen D A, Ouchi T, et al. Calcium-bismuth electrodes for large-scale energy storage (liquid metal batteries)[J]. Journal of Power Sources, 2013,241:239-248.
[49]	Sudworth J L. Sodium/nickel chloride (ZEBRA) battery[J]. Journal of Power Sources, 2001,100(1/2):149-163.
[50]	Coetzer J. A new high energy density battery system[J]. Journal of Power Sources, 1986,18(4):377-380.
[51]	Lu X C, Xia G G, Lemmon J P, et al. Advanced materials for sodium-beta alumina batteries: Status, challenges and perspectives[J]. Journal of Power Sources, 2010,195(9):2431-2442.
[52]	Hosseinifar M, Petric A. High temperature versus low temperature Zebra (Na/NiCl₂) cell performance[J]. Journal of Power Sources, 2012,206:402-408.
[53]	Ao X(敖昕), Wu X W(吴相伟), Wu T(吴田), et al. Operating temperature on cathode material and electrochemical performance of Na-NiCl₂ batteries[J], Journal of Inorganic Materials (无机材料学报), 2017,32(12):1243-1249.
[54]	Lu X C, Li G S, Kim J Y, et al. The effects of temperature on the electrochemical performance of sodium-nickel chloride batteries[J]. Journal of Power Sources, 2012,215:288-295. doi: 10.1016/j.jpowsour.2012.05.020 URL
[55]	Virkar A V, Viswanathan L, Biswas D R. On the deterioration of β-alumina ceramics under electrolytic conditions[J]. Journal of Materials Science, 1980,15(2):302-308. doi: 10.1007/PL00020062 URL
[56]	Hu Y, Wen Z Y, Wu X W, et al. Nickel nanowire network coating to alleviate interfacial polarization for Na-beta battery applications[J]. Journal of Power Sources, 2013,240:786-795.
[57]	Breiter M W, Dunn B, Powers R W, et al. Asymmetric behavior of β″-alumina[J]. Electrochimica Acta, 1980,25(5):613-616.
[58]	Bugden W G, Barrow P, Duncan J H. The control of the resistance rise of sodium sulphur cells[J]. Solid State Ionics, 1981,5:275-278.
[59]	Reed D, Coffey G, Mast E, et al. Wetting of sodium on β''-Al₂O₃/YSZ composites for low temperature planar sodium-metal halide batteries[J]. Journal of Power Sour-ces, 2013,227:94-100.
[60]	Lu X C, Li G S, Kim J Y, et al. Liquid-metal electrode to enable ultra-low temperature sodium-beta alumina batteries for renewable energy storage[J]. Nature Communications, 2014,5:4578. doi: 10.1038/ncomms5578 URL pmid: 25081362
[61]	Ignaszak A, Pasierb P, Gajerski R, et al. Synjournal and properties of Nasicon-type materials[J]. Thermochimica Acta, 2005,426(1/2):7-14.
[62]	Gao X P, Hu Y Y, Li Y, et al. A high-rate and long-life intermediate-temperature Na-NiCl₂ battery with dual-fun-ctional Ni-carbon composite nanofibers network[J] ACS Applied Materials & Interfaces 2020,12(22):24767-24776. doi: 10.1021/acsami.0c04470 URL pmid: 32406671
[63]	Ao X, Wen Z Y, Hu Y Y, et al. Enhanced cycle performance of a Na/NiCl₂ battery based on Ni particles encapsulated with Ni₃S₂ layer[J]. Journal of Power Sources, 2017,340:411-418.
[64]	Jin Y, Liu K, Lang J L, et al. An intermediate temperature garnet-type solid electrolyte-based molten lithium battery for grid energy storage[J]. Nature Energy, 2018,3(9):732-738.
[65]	Yin H Y, Chung B, Chen F, et al. Faradaically selective membrane for liquid metal displacement batteries[J]. Nature Energy, 2018,3(2):127-131.
[66]	Bronstein H R, Bredig M A. The electrical conductivity of solutions of alkali metals in their molten halides[J]. Journal of the American Chemical Society, 1958,80(9):2077-2081.
[67]	Ukshe E A, Bukun N G. The dissolution of metals in fused halides[J]. Russian Chemical Reviews, 1961,30(2):90-107.
[68]	Masset P. Iodide-based electrolytes: A promising alternative for thermal batteries[J]. Journal of Power Sources, 2006,160(1):752-757. doi: 10.1016/j.jpowsour.2006.01.014 URL
[69]	Sangster J, Pelton A D. Phase diagrams and thermodynamic properties of the 70 binary alkali halide systems having common ions[J]. Journal of Physical and Chemical Reference Data, 1987,16(3):509-561. doi: 10.1063/1.555803 URL
[70]	Masset P, Schoeffert S, Poinso J Y, et al. Retained molten salt electrolytes in thermal batteries[J]. Journal of Power Sources, 2005,139(1/2):356-365.
[71]	Sridhar R, Johnson C E, Cairns E J. Phase diagrams of the systems LiI-KI and LiI-RbI[J]. Journal of Chemical & Engineering Data, 1970,15(2):244-245.
[72]	Janz G J, Tomkins R P T, Allen C B, et al. Molten-salts: Volume 4, Part 3, bromides and mixtures - iodides and mixtures - electrical conductance, density, viscosity, and surface-tension data[J]. Journal of Physical & Chemical Reference Data, 1977,6(2):409-596.
[73]	Masset P, Guidotti RA. Thermal activated (thermal) battery technology-Part II. Molten salt electrolytes[J]. Journal of Power Sources, 2007,164(1):397-414.
[74]	Masset P. Iodide-based electrolytes: A promising alternative for thermal batteries[J]. Journal of Power Sources, 2006,160(1):688-697.
[75]	Kaun T D. Li-Al/FeS₂ cell with LiCl-LiBr-KBr electrolyte[J]. Journal of the Electrochemical Society, 1985,132(12):3063-3064. doi: 10.1149/1.2113726 URL
[76]	Vissers D, Redey L, Kaun T. Molten-salt electrolytes for high-temperature lithium cells[J]. Journal of Power Sour-ces, 1989,26:37-48.
[77]	Johnson C E, Hathaway E J. Lithium hydride systems: solid-liquid phase equilibria for the ternary lithium hydride-lithium chloride-lithium iodide system[J]. Journal of Chemical & Engineering Data, 1969,14(2):174-175.
[78]	Kelley D H, Weier T. Fluid mechanics of liquid metal batteries[J]. Applied Mechanics Reviews, 2018,70(2):020801. doi: 10.1115/1.4038699 URL
[79]	Weber N, Galindo V, Stefani F, et al. Numerical simulation of the Tayler instability in liquid metals[J]. New Jour-nal of Physics, 2013,15(4):043034.
[80]	Stefani F, Weier T, Gundrum T, et al. How to circumvent the size limitation of liquid metal batteries due to the Tayler instability[J]. Energy Conversion and Management, 2011,52(8/9):2982-2986.
[81]	Weber N, Galindo V, Stefani F, et al. Current-driven flow instabilities in large-scale liquid metal batteries, and how to tame them[J]. Journal of Power Sources, 2014,265:166-173.
[82]	Herreman W, Nore C, Cappanera L, et al. Tayler instability in liquid metal columns and liquid metal batteries[J]. Journal of Fluid Mechanics, 2015,771:79-114. doi: 10.1017/jfm.2015.159 URL
[83]	Personnettaz P, Landgraf S, Nimtz M, et al. Mass transport induced asymmetry in charge/discharge behavior of liquid metal batteries[J]. Electrochemistry Communications, 2019,105:106496.
[84]	Jiang Y D, Cao T Y, Song P D, et al. Effects of magnetically induced flow on electrochemical reacting processes in a liquid metal battery[J]. Journal of Power Sources, 2019,438:226926.
[85]	Wen Z Y(温兆银), Lin Z X(林祖镶), Gu Z H(顾中华), et al. Behavior of ZrO₂ in β-Al₂O₃ ceramics[J]. Acta Materiae Compositae Sinica (复合材料学报), 1996,13(3):39-43.
[86]	Hayashi A, Noi K, Sakuda A, et al. Superionic glass-ceramic electrolytes for room-temperature rechargeable sodium batteries[J]. Nature Communications, 2012,3:856. doi: 10.1038/ncomms1843 URL pmid: 22617296
[87]	Nicholas M G, Crispin R M. Diffusion bonding stainless steel to alumina using aluminium interlayers[J]. Journal of Materials Science, 1982,17(11):3347-3360.
[88]	Huang Y, Wen Z Y, Yang J, et al. La_0.8Sr_0.2Co_0.3Fe_0.7O₃-_δ as a novel candidate coating material for the positive current collector in sodium sulfur battery[J]. Electrochimica Acta, 2010,55:8632-8637.
[89]	Pa N, Barney D, Steunenberg R, et al. High-performance batteries for electric-vehicle propulsion and stationary energy storage[D]. Argone Ill, Argonne National Laboratory, 1978.
[90]	Song S F, Wen Z Y, Liu Y, et al. New glass-ceramic sealants for Na/S battery[J]. Journal of Solid State Ele-ctrochemistry, 2010,14(9):1735-1740.
[91]	Ouchi T, Sadoway D R. Positive current collector for Li\|\|Sb-Pb liquid metal battery[J]. Journal of Power Sour-ces, 2017,357:158-163.

Cathode candidate	Melting point/^oC	Density/ (g·cm^-3)	Cost/ (￥·mol^-1)	OCV/ V(vs. Li/Li⁺)	Average OCVa	Alloy stoichiometry	Reported chemistry
Te	449.5	6.24	50.7	~ 1.7 V	> 1.5 V	Li₂Te	Li-Te^[22,24-25]
Bi	271.3	10.05	7.1	~ 0.95 V	< 0.8 V	Li₃Bi	Li-Bi^[23] Na-Bi^[25]
Sb	630.7	6.70	4.3	~ 0.92 V	~ 0.9 V	Li₃Sb	Li-Sb^[21] Ca-Sb^[26]
Sn	231.9	5.75~7.28	16.5	~ 0.80 V	~ 0.42 V	Li₂₂Sn₅	Li-Sn^[27] Na-Sn^[28]
Pb	327.5	11.34	3.2	~ 0.75 V	~ 0.50 V	Li₇Pb₂	Li-Pb^[29]

Electrolyte	Compositon/mol.%	Melting point/^oC	Density		Ionic conductivity at 475 ^oC/(S·cm^-1)
Electrolyte	Compositon/mol.%	Melting point/^oC	25 ^oC	500 ^oC	Ionic conductivity at 475 ^oC/(S·cm^-1)
LiCl-KCl	58.8-41.2	352^[69]	2.01	1.59~1.6^[70]	1.69^[68], 1.57 (450 ^oC)
LiI-KI	63.3-36.7	288^[71]	3.53	2.77~2.83^[72]	1.56^[68], 2.24 (607 ^oC)
LiCl-LiI	34.6-65.4	368^[69]	3.17	2.57	3.88[68], 3.5 (450 ^oC)
LiF-LiCl	30.5-69.5	501^[69]	2.17	--	--
LiBr-RbBr	42-58	271^[72]	3.38	2.63 (647 ^oC)	1.33(567 ^oC)^[73]
LiCl-KCl-CsCl	57.5-13.3-29.2	265	2.23	--	0.28 (280 ^oC)^[73]
LiF-LiCl-LiBr	22-31-47	443	2.91	2.17-2.19^[70]	3.21^[68]
LiF-LiBr-KBr	2.5-60-37.53-63-34	324^[74]312^[74]	3.093.12	--	1.56^[68]1.75^[74]
LiCl-LiBr-KBr	25-37-38	310^[75,76]	2.85	--	1.7
LiCl-LiBr-LiI	10.0-16.1-73.9	368	3.40	--	3.68^[68]
LiF-LiCl-LiI	11.7-29.1-59.2	341^[77]	3.53	2.69^[70]	2.77^[68]
NaF-NaCl-NaI^[24]	15-32-53	530	2.90	2.54(560 ^oC)	1.7-2.0(560 ^oC)
NaCl-KCl-MgCl₂^[44]	30-20-50	396	2.10	--	--
LiCl-NaCl-CaCl₂^[48]	38-27-35	450	2.14	1.9	2.18
LiCl-NaCl-CaCl₂-BaCl₂^[48]	29-20-35-16	390	2.53	2.24(600 ^oC)	1.9(600 ^oC)
LiCl-NaCl-KCl	55-9-36	346	--	--	1.50(450 ^oC)